Structural panels

ABSTRACT

Improved Structural Panels for use in the construction industry capable of withstanding greater compressive and shear forces than those presently available. This increased capacity to withstand vertical loading allows the Structural Panels to be used in multi-story buildings. 
     The Structural Panel is comprised of facings 1 and 2, a honeycomb core 3, two vertical support 4 and 5, and a horizontal support 6. Glue is used to hold the assembly together and to provide for the even distribution of compressive forces. Nails, screws, or glue are used during construction to secure the panels to each other and to the framework of the building structure.

TECHNICAL FIELD

This invention relates to an improvement in prefabricated structuralpanels and more particularly to such panels having a honeycomb core usedas structural units in the building industry.

BACKGROUND ART

Structural panels, generally consisting of a honeycomb core covered onthe front and back with facings such as plywood are well known. Thefacings, both front and back, are nailed during the construction processto the vertical studs of the building structure. They are likewisenailed to the wood base plate and to upper plates which are installedduring construction. The honeycomb core, usually made a resinimpregnated heavy paper gives the panel structural strength and iscommonly glued to the front and back sheets.

The core also provides thermal and acoustic insulation and may beutilized to support additional insulation. Insulating material, such ascellulose fiber, may be deposited in the cavities of the cellular core.Any type of insulation can be used including plastic foams and mineralfiber.

The honeycomb core gives strength to the panel by keeping the front andback facings parallel, thereby preventing them from flexing under thecompressive forces of the weight they support.

Such structural panels lack the strength necessary to provide structuralsupport to multi-story buildings. They are typically difficult toinstall properly and lack the flexibility required for on-sitemodification such as would be required to add windows or doors.

Also, the allowed capacities of such panels to withstand the structuralloads imposed upon them is presently determined by the number of nailsfastening the panels to the studs and plates of the building frame.Although panels which are both nailed and glued together consistentlywithstand vertical testing loads of 40,000 pounds (18,144 kilograms) perpanel, the building codes will only allow the nailing schedule todetermine the allowable vertical loading. With the maximum practicalnailing schedule of 2 inches (5 centimeters) between nails around theperimeter of each panel, the allowed load is only 12% of the test load.The building codes recognize only the load limit of a panel with nailsalone even though the assembly can utilize both glue and nails to attachthe panels to the framing members. They will recognize the load valuesfor glued assemblies only if no nails are used. This invention willallow the utilization of the full strength of the panel as given byactual experimental test results.

A prior art search did not disclose any patents for structural panelswhich provide increased strength, ease of installation, and flexibilityin use, in the manner of this invention. The following U.S. patentdocuments were considered in the investigation and evaluation of theprior art relative to this invention.

    ______________________________________                                        U.S. Pat. No.                                                                              INVENTOR      ISSUE DATE                                         ______________________________________                                        2,809,403    Clements      15 October 1957                                    2,893,076    Herts          7 July 1959                                       3,616,139    Jones         26 October 1971                                    3,665,662    Timbrook      30 May 1972                                        3,970,502    Turner        20 July 1976                                       ______________________________________                                    

The Clements patent discloses a structural panel primarily for use as adoor. It utilizes a honeycomb core. It is concerned mainly with a methodof obtaining maximum strength from the honeycomb core but is notparticularly concerned with vertical loading. Specifically, it does notapproach the problem of vertical stresses in the manner of the presentinvention.

The Herts patent discloses structural panels having a honeycomb corewhich are intended primarily as doors or table tops.

The Jones patent discloses multilayered thermal insulators which utilizemultiple honeycomb structures and is primarily concerned with theinsulating properties of the panel.

The Timbrook patent discloses a structural panel utilizing a honeycombcore. It is primarily concerned with providing a method ofinterconnecting the panels to facilitate on-site construction withprefabricated panels.

The Turner patent discloses a structural panel having a foam core. It isprimarily concerned with preventing delamination of the outer coveringsfrom the core and with providing an improved latching method forinterconnecting panels.

All the above mentioned panels lack the structural strength required towithstand the vertical stresses of use in multi-story buildings. They donot lend themselves to easy on-site modification and they present acomparatively high degree of difficulty in their installation.

DISCLOSURE OF THE INVENTION

The object of this invention is to provide a Structural Panel havingimproved strength characteristics to allow the use of such panels inmulti-story buildings.

Another object of this invention is to provide a prefabricatedStructural Panel which can be easily modified on-site to allow for doorsand windows.

Yet another object of this invention is to provide a Structural Panelwhich is comparatively easier to install than those in current use.

Those objects are attained through the use of structural adhesive toattach the facing panels to the frame of the structural panel andthrough the construction of structural panels having their lower edgespre-aligned so as to provide the proper clearance between themselves andthe foundation. This pre-alignment of the panel's lower edges also causethe panel to be properly positioned vertically. Imbedded I-beam headerconstruction in one embodiment of this invention allows that embodimentto be modified to contain openings for doors or windows without loweringthe vertical load capacity of the structural panel.

The materials used in panel construction vary. The facings may made ofplywood, waferboard, particle board, metal sheet, gypsum board, or otherstructural siding. The horizontal members and vertical supports may bemade of wood, sheet metal channels, rectangular metal tubing, or otherstructural materials.

A pin assembly provides a means of connecting the structural panels toeach other. The provides improved shear strength which makes the panelsignificantly more resistant to loads such as those introduced byearthquakes.

These Structural Panels may be nailed, screwed, or glued to thefoundation plate. An alternate method of attaching the panels to thefoundation plate is provided where a bracket on the bottom of one of thepanel's vertical supports has a bolt passing through its lower surfaceand into a section of metal channel in the foundation plate. The bolt issecured into the channel with an elongated nut in the manner commonlyused to secure structure to such types of channel. The channel may beembedded in a wood foundation plate to provide a higher resistance toheat flow than would be afforded if the channel were not embedded in awood foundation plate. A channel may be used without a wood foundationplate in applications where heat flow through the channel would not bedetrimental.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary perspective front view of the basic structuralpanel.

FIG. 2 is a fragmentary perspective front view of the structural panelhaving an I-beam header.

FIG. 3 is a perspective view of the mount bracket as it is attached tothe lower end of a vertical support.

FIG. 4 is a perspective view of the bolt and elongated nut which attachthe mount bracket to the channel in the foundation plate.

FIG. 5 is a top view of the elongated nut of FIG. 4.

FIG. 6 is a fragmentary perspective view of the foundation platecontaining the section of channel.

FIG. 7 is a perspective view of the foundation plate of FIG. 6 showingthe anchor bolts.

FIG. 8 is a perspective view of the pin.

FIG. 9 is a side view of the mount bracket showing the attachment of thepanel's vertical support to the foundation plate.

BEST MODE FOR CARRYING OUT THE INVENTION

As can be seen in FIG. 1, two vertical supports 4 and 5 and an upperhorizontal member 6 are glued to each other and glued to two coveringsheets referred to as sheets of plywood 1 and 2. The frame does notinclude a member along the bottom of the unit. The gluing provides foreven distribution of the vertical loading, thereby allowing thestructural panel to support much greater weight than it otherwise could.

An inner core of honeycomb paper 3 is glued to the inner surfaces ofeach sheet of plywood 1 and 2. The honeycomb core 3 provides additionalstructural strength because it prevents the plywood sheets 1 and 2 fromflexing under vertical loading.

The lower edges 11 and 12 of the plywood sheets 1 and 2 extend downwardbeyond the lower ends 10 and 13 of the vertical support members of theframe 4 and 5. This allows the lower edges 11 and 12 of the plywoodsheets 1 and 2 to rest just above the level of the buildings foundationwhen the lower ends 10 and 13 of the vertical support members 4 and 5rest upon the foundation plate. This is important because it preventsthe plywood sheets 1 and 2 from contacting the foundation where they mayabsorb water which may result from spills or mopping. This prealignmentof the lower edge of the plywood sheets 11 and 12 relative to thefoundation greatly simplifies installation of the Structural Panels.Panels presently in use must be held in place with the proper clearancebetween their lower edge and the foundation while they areinterconnected.

The vertical supports 4 and 5 are positioned relative to the two sheetsof plywood 1 and 2 so as to provide a tongue and groove vertical matingsurface which facilitates simplified panel installation and forms aweatherproof joint between panels.

Holes 7, 8, and 9 are provided in both of the vertical support members 4and 5. A pin arrangement is shown in FIG. 8 which utilizes these holes7, 8, and 9 to connect the structural panels to each other. The pin 32fits into one of the holes 7, 8, or 9 on one of the vertical supportmembers 4 or 5 and into a corresponding hole on an adjacent structuralpanel.

As shown in FIG. 2, a cross-member 18 and inside sheet of plywood 14provide structural support for overhead loads in order to allow thisembodiment of the structural panel to have an opening for a window ordoor cut into it. Members 15, 16, and 17 are the framework of a windowin this embodiment.

The inside sheet of plywood 14 fits into a slot 19 in the cross member18. A slot is likewise provided in the upper horizontal member 6 andboth vertical supports 4 and 5. The inside sheet of plywood 14 is gluedinto each of the slots provided forming a structural I section. Theslots may be offset toward the weaker of the facings if two differentthicknesses of plywood are used.

A lower horizontal member 35 may be used to add strength to thisembodiment of the Structural Panel.

In use, the Structural Panels as described are placed upon thefoundation plate which generally consists of a wood two by four securedto the foundation of a building. A first panel can be nailed to thefoundation plate and then successive panels nailed to the first panel aswell as the foundation plate as they are installed. Then a top plate,generally a two-by-four, is placed along the tops of the StructuralPanels, laying upon the top of the upper horizontal member 6, and nailedin place. When required, two top plates may be installed along the topof the panels to resist high building stresses. If metal plates areused, self tapping screws may be used as fasteners.

FIG. 3 shows an alternate method of attaching the Structural Panels tothe foundation plate. A mount bracket 20 is attached to the lower end 10of a wood vertical support 5 with glue or nails through holes 21, 22,and 23. If metal vertical supports are used, the bracket 20 would be anintegral part of the support. One such mount bracket 20 can be used onthe right vertical support of each panel to secure that panel to thefoundation plate. Since the right vertical support 5 of one panel isdirectly adjacent to the left vertical support 4 of the panel to itsright, only one mount bracket 20 is required for each panel. That singlemount bracket 20 therefore actually secures two panels to the foundationplate because the adjacent panels are secured to each other.

A bolt 25 extends through the hole 24 in the bracket 20. An elongatednut 26 engages the bolt 25 as shown in FIG. 4.

The bolt 25 extends into a section of channel 27 within the foundationplate 28 shown in FIG. 6. The elongated nut 26, as shown in the top viewof FIG. 5, will enter the channel if oriented along its longitudinalaxis and then will turn to prevent its retraction when the bolt 25 istightened.

FIG. 7 shows the foundation plate 28 with the channel 27. Also shown arethe anchor bolts 30 by which the foundation plate 28 is secured to thefoundation. A hole 29 (as shown in FIG. 6) in the foundation plate 28 isprovided for the anchor bolts 30. The head of an anchor bolt 30 can beseen extending through the foundation plate 28 in FIG. 7.

FIG. 9 shows the Structural Panel secured to the foundation plate 28.Note that the lower edges 11 and 12 of the plywood facings 1 and 2 areslightly higher that that lower surface 34 of the foundation plate 28.The lower surface 34 of the foundation plate 28 rests upon thefoundation. The lower edges 11 and 12 of the plywood facings 1 and 2 arekept above the lower surface 34 of the foundation plate 28 to preventthe plywood facings 1 and 2 from absorbing water which may be presentupon the foundation as described above. The distance between the loweredges 11 and 12 of the plywood facings 1 and 2 and the lower surface 34of the foundation plate should be approximately 1 centimeter (3/8 inch).

FIG. 8 show the pin 32 having a washer 33. Pins may be inserted into theholes 7, 8, and 9 in the vertical supports 4 and 5 to give the connectedStructural Panel greater shear strength. The washer 33 allows the pin 32to be inserted to the proper depth.

I claim:
 1. A structural panel for use in the building industryutilizing foundation plates comprising:(a) two vertical support membershaving upper and lower ends, (b) an upper horizontal member secured tosaid two vertical support members with glue, (c) a covering sheet oneither side of said vertical support members and said upper horizontalmember, attached to said vertical support members and said horizontalmember with glue said covering sheet on either side extend downwardbeyond the lower ends of the vertical support members such a distancethat when the lower ends of the vertical support members rest upon thefoundation plate the lower ends of the covering sheets are approximatelyone centimeter (3/8 inch) above the foundation, and (d) a honeycomb corewhich is glued to both of said covering sheets.
 2. A structural panelfor use in the building industry utilizing foundation platescomprising:(a) two vertical support members having upper ends and lowerends each having one or more holes through which pins may be inserted,(b) an upper horizontal member secured to said two vertical supportmembers with glue, (c) a crossmember between said vertical supports, (d)a lower horizontal member disposed between the lower ends of saidvertical support members, (e) a mount bracket attached to the lower endsof said vertical support member creating a bottom surface, (f) a sectionof channel embedded into said foundation plate, and a plurality of nutsand bolts attaching said mount bracket to said section of channel, (g) acovering sheet on either side of side vertical support members and saidupper horizontal member, attached to said vertical support members andsaid horizontal member with glue, said covering sheet on either sideextend downward beyond the lower ends of the vertical support memberssuch a distance that when the lower ends of the vertical support membersrest upon the foundation plate the lower ends of the covering sheets areapproximately one centimeter (3/8 inch) above the foundation, (h) ahoneycomb core glued to both of said covering sheets, and (i) aplurality of pins within said holes to secure one structural panel toanother structural panel.
 3. A method of constructing structural panelsfor use in the building industry utilizing foundation plates, whichcomprises the steps of:(a) gluing two vertical support members to anupper horizontal member forming a structure having a first and secondside with an upper and lower end; (b) gluing a first covering sheet tothe first side of the two vertical support members and the horizontalmember; (c) gluing a honeycomb core to the first covering sheet; (d)gluing a second covering sheet to the second side of the two verticalsupport members and the horizontal member and to the honeycomb core saidfirst and second covering sheets are glued to said two vertical supportssuch that their lower surfaces extend downward beyond the lower ends ofthe vertical support members such a distance that when the lower ends ofthe vertical support members rest upon the foundation plate the lowerends of the covering sheets are approximately one centimeter (3/8 inch)above the foundation.
 4. A method for constructing Structural Panelsaccording to claim 3 further comprising the step of drilling one or moreholes in the two vertical support members to accommodate one or morepins for connecting one Structural Panel to another Structural Panel.